Drag testing apparatus



A ril 16,1946. ELL 2,398,574

' I .DRAG TESTING APPARATUS I Filed Feb. 23, 1945 8 Sheets-Sheet 1 &

i JOHN/V 55 I;

'April16, 1946. J. M. BELL 8, 7

' DRAG TESTINGHAPPARATUS Filed Feb. 23 1945 8 Sheets-Sheet 2 21 3mm; JOHN M BELL April 16, 1946. J BELL 2,398,574

DRAG TESTING APPARATUS Filed Feb/23, 1945 8 Sheets-Sheet 3 Jamv/W. 5541.

April 16, 1946. J, M, BELL 2,398,574

DRAG TESTING APPARATUS Filed Feb. 23, 1945 I 8 Sheets-Sheet 4 April 16, 1946. A J; BELL 2,398,574

I DRAG TESTING APPARATUS April 16, 1946. H J; M, BELL 2,39s,574

DRAG TESTING APPARATUS' Filed Feb. 25, 1945 8 Sheets-Sheet 8 gazes 3mm: JOHN M BfLL Patented Apr. 16, 1946 UNITED STATES PATENT OFFICE DRAG TESTING APPARATUS John M Bell, Chester, s. 0. Application February 23, 1945,:seria1Ne. 579,401 l 17 Claims.

This invention relates to an apparatus for constantly determining the viscosity in a fluid and indicating as to whether the viscosity is increasing or decreasing, together with means for varying the amount of pressure applied to the means submerged in the liquid for varying the amount of torsion or driving effect on the means for driving the member disposed within the fluid which is being tested. 1

It is an object of this invention to provide testing means for constantly testing and indi cating the smoothness of a surface which is being tested. i

It is another object of this invention to provide apparatus for continuously and constantly testing viscosity, smoothness of surface and the like, and indicating any changes which may occur therein with compensating means for varying the driving effect of the apparatus on the testing tool in accordance with changes in viscosity; smoothness of surface and the like. i

It is another object of this invention to provide means for continuously testing the magnetic characteristics of a metal. A

Some of the objects of the invention having been stated, other objects will appear as th description proceeds when taken in connection with the accompanying drawings in whicht Figure 1 is a side elevation of the apparatus;

Figure 2 is a front elevation of the apparatus looking from the left hand side of Figure 1;

Figure 3 is a top plan view of the apparatus;

Figure 4 is an elevational view looking from along the line 4-4 in Figure 2 Figure 5 is a horizontal sectional view taken along the line 5-5 in Figures 4 and 6 Figure 6 is a vertical sectional View taken along the line 66 in Figure 1;

Figure 7 is an elevation taken partly in section and along the line in Figure 1;

Figure 8 is a vertical sectional view on an enlarged scale and taken along the line 88 in Figure 1; A t

Figure 9 is an elevational view looking from along the line 9-3 in Figure 7 Figure 10 is an elevational view looking from along the line |IJ| in Figure 7;

Figure 11 is a sectional view taken along the line inFigure Figure 12 is a sectional view taken along the line |2--| 2 in Figure 5;

Figure 13 is a sectional view taken alongthe line |3-| 3 in Figure 3; a

Figure 14 is. a sectional viewtaken along the line |4| |inFigure 3;

Figure 15 is a wiring diagram of the apparatus; Figure 16 is a view looking upward along the line |6|B in Figures 2 and 6;

Figurev 1'7 is an isometric view showing the lower end of the apparatus with the paddle disposed in a containerhaving a liquid therein;

Figure 18 is a view of the lower end of the apparatus showing a brush H1 in contact with the surface of a member 9 being tested;

Figure 19 is a longitudinal sectional view through one of the counter solenoids: A

Figure 20 shows another form of testingtuol. Referring more specifically to the drawings,;the numeral It] indicates a base framework having suitable legs extending downwardly therefrom to the floor, not shown, for supporting the, ap-

paratus above the floor sothat the testing'de vice on the lower end of the testing; apparatus may be positioned a substantial distance above the floor.

A pair of electric wires 2 and I3 are connected to any suitable source of electric current and wire I 2 has a switch l4 therein: These wires lead to an electric motor;|5.which is mounted on the frame II]. This motor has a motor shaft IE on which a pulley I1 is mounted, the pulley having a belt I8 mounted thereon, which is also mounted on a pulley l9 on a worm shaft 20 mounted in a suitable housing 2|.

The housing 2| has a base portion 22, integral therewith which rests on the framework l0. Rotatably mounted in the housing 2| isa vertically disposed tube 25, which is surrounded by a suitable packing box 26 integral with the upper surface of the base portion 22 of the housing and threadably secured on thisprojectionZB is a cap 21 and suitable packing material 28 is d sposed between cap 27 and .packing box 26 for preventing leakage of oil and other; fluid which might be disposed within the housing 2|. This permits rotation of the tube 25 in the packing box;

Fixedly secured on the tube 25 is a'worm wheel 29 which meshes with a worm 30 on shaft 20. Rotation of shaft 20 when the motor v 5 is operating will impart rotation tothetube25. The tube 25 projects upwardly through the; top of the housing 2| and has fixedly secured thereon an insulation disk 3| having a pair of annular metallic bands 32 and 33 mounted on the lower surface thereof. A l

A suitable conductor wire 36 is connected to the outer annular metallic band 33 and a conductor wire 35 is connected to the inner metallic band 32, which wires at their other ends are connected in a manner-to be later described.

Mounted on one side of the housing 2| is an insulation block 31 which has a pair of metallic brushes 38 and 39 mounted thereon, the brush 38 contacting the outer metallic band 33 and the brush 39 contacting the inner metallic band 32. A wire 4| leads from brush 38 to a counting mechanism to be presently described, while the wire 40 is connected to the brush 39 and leads to a connection to be later described.

The tube 25 has fixedly secured thereon a circular plate .45 forming the lower part of what I term a revolving cage. There is also an upper circular plate 46. Plate 46 which forms a part of the cage is mounted on a plurality of uprising posts 41 and spacers 48 surround these posts and are disposed between the lower plate 45 and the upper plate 46 for supporting the plate 46. The

plate 46 is threadably secured on a tube 50 which projects upwardly a substantial distance.

This tube 50 has mounted thereon for vertical sliding movement, a tube 5| having a pair of pins 52 and 53 projecting laterally therefrom which are adapted to be engaged by a swinging member associated with certain solenoids which will be presently described.

The tube 25 project upwardly a substantial distance above the upper surface of lower plate 45 and has rotatably mounted thereon a tubular member 55 which has a worm wheel 56 integral therewith. This sleeve or tubular member 55 has secured therein a plug 51 by means of. a et screw 58. In the lower end of plug 51 is fixedly secured by soldering, welding or the like, a torsion wire 59. The worm gear 56 meshes with a suitable worm 69 on a shaft 6|, which is rotatably mounted in bearings 52 and 59 mounted on the upper surface of lower cage plate 45. This shaft 6| has fixedly secured thereon ratchet wheels 63 and 64, the upper portions of which are engaged by operating members 65 and 66.

It will be observed, especially in Figures 11 and 12, that these ratchet wheels are opposite hand and are adapted to rotate the shaft 6| in opposite directions. The operating member 65 has an open ended slot 61 in its free end, and a cross bar l4'of'this s1ot is adapted to engage against a tooth in the ratchet wheel and rotate theshaft 6|"one notch when the operating member 65 is moved toward the observer in Figure 5 or to the right in Figure 12.

The operating member 66 also has a slot 66 having a cross bar 75 and when it is moved to the left in Figure 11 or away from the observer in Figure 5, it will rotate the shaft 6| one notch in anopposite direction to that which the first ratchet wheel 63 is adapted to rotate the shaft 6 I.

The other ends of the operating members 65 and 65 are pivotally connected as at m and H to the free ends of levers l2 and 73 which are fixedly secured on oscillating shafts l8 and 19. The levers I2 and I3 have downwardly projecting tubular portions 16 and I1 which are fixedly secured to vertically disposed shafts l8 and 19.

The shafts I8 and 19 are turnably mounted in the upper and lower cageuplates 46 and 45 respectively and project upwardly a substantial distance and have the tubular portions 82 and 83 of levers 84 and-85 fixedly secured thereto.

Between the cage plate 46 and the levers l2 and I3 there are spacer members 42 and 48 disposed on shafts l8 and 19. p I

The levers 84 and 85 are normally held against stops 86 and 81 by means of tension springs 98 and 89 (Fig. 8) whose other ends are secured to the top surface of upper cage plate The sleeve 5| has a pair of projections 90 and 9| integral therewith and which are adapted to be engaged by the free ends of levers 64 and except when the sleeve 5| is in neutral position as shown in Figure 4.

When the sleeve 5| is in lowered position, and the tube 25 and the cage, including plates 45 and 46 are rotating in a counterclockwise direction in Figure 3, the projections and 9| will be engaged by the lever 84 and the lever 84 will be swung on its pivot twice during each revolution of the cage. This will cause the lever to momentarily engage a metallic leaf spring 93 and complete a circuit to be presently described and when the lever has passed by each projection it Will be drawn back to normal position by means of its spring 88.

When the sleeve 5| is in raised position it will cause the projections 90 and 9| to be engaged by the lever 85 and swing the lever 85 into contact with a leaf spring contact member 92 to complete a circuit to be described.

The tube 25, after passing out of the lower end of the housing 2|, has fixedly secured thereon by means of a set screw 94, an insulation block 95 which has metallic bands 96 and 91 secured therearound to which are secured wires 99 and 98 respectively, which lead to contact points |9| and I99 respectively mounted on blocks I03 and H32 respectively.

Disposed immediately below the pipe 25 is a similar pipe 25A (Fig. 8) through which the torsion wire 59 extends and the lower end of the torsion wire is fixedly secured in a block l65, which is fixed in tube 25A by means of a set screw I96.

Fixedly mounted on the tube 25A is a metallic circular member I91 which has mounted thereon and in electric communication therewith a pair of contact points I08: and [09. The framework includes a substantially horizontal support H0, in which the lower end of tube 25A is rotatably mounted.

The tube 25A is supported for rotation on support ||0 by means of a collar H2, being fixedly secured thereon by means of a set screw H3 passing through. collar H2 and tube 25A. Set screw H3 also secures a rod '4 in position and this rod has a suitable paddle ||5 on the lower end thereof, which is adapted to be placed in a fluid for testing the fluidity or the viscosity thereof.

In Figure 1'7 I show a suitable container H6 in which the paddle H5 may operate with the paddle being shown in somewhat difierent shape in Figure 17, but the shape of the paddle is not important. The fiuid'line incontainer I I6 is indicated by reference character I Hi.

Immediately below the support Hi] there is adapted to be secured on rod 4 a grooved wheel I29 having a V-shaped groove |20A in its periphery so that instead of having the paddle H5 in a fiuid, the size of a string, wire, strand or other elongated object may be measured by the apparatus by the radial distance of the same from the center of shaft ||4.

Instead of having paddle I I5 on its lower end for entering a fluid to test the viscosity thereof, I may have a permanent magnet H5 which can be passed into close proximity to a metallic member |'|6 to determine the magnetic properties thereof.

When using a grooved wheel I20 for measuring the size of a wire. or strand of yarn in a manufacturing process, for example, the strand or wire can be continuously passed through the groove while the apparatus is operatingpand the larger the strand or wire is at a givenpoint, the further out in the groove towards the periphery of wheel I will it be positioned, and this will increase the drag exerted on the rotation of the wheel, which will in turn increase the torsion in the torsion wire 59, and, of course,-if places occur in the strand or wire whichare of smaller diameter, the strand or wire will then occupy a position closer to the bottom of the groove and less torsion will be exerted by this frictional contact.

, Secured on the lower surface of frame I0 is an insulation block I2I on which are secured metall'icleaf spring contact brushes I22 and I23. These are adapted to press against the metallic rings ;.96 and 91 on the insulation block 95 at] all times.

Secured on the upper surface of horizontal frame I0 is an inverted U-shaped strap member 124. On one leg of this strap member there is a bar I25 on which is secured solenoids I26 and I21. Pivotably mounted in and spanning the distance transversely between the vertical legs of inverted U-shaped member I24 is a cross rod I28, which has fixed thereon a member I29 projecting forwardly and rearwardly of rod I28 and to each endof this member I29 there is pivotally connected the upper ends of the slidable cores I30 and I3I of the solenoids I26 and I21. Also fixed on the transverse rod I28 is a lever I33, which has a balancing weight I34 at one end and has a fork comprising portions I35 and I36 at its other end which have slots I31 in their free ends fitting over the projections or pins 52 and 53' on the sleeve member 5I.

Mounted on the top surface of inverted U- shaped member I24 is a supporting bar I40, which has mounted thereon, a pair of bearings MI and I42 in which a rod I43 is rotatably mounted. This rod has a pair of ratchet wheels I44 and, I45 fixed thereon which are adapted to be engaged by the forked ends of solenoid cores I46 and I41. These extend into solenoids I48 and I49 respectively and are normally pulled back to nor mal position by means of tension springs I50 and I5I, having their ends secured to the solenoid shell and to the solenoid core. When the sole noids are energized the cores I46 and I41 are moved to engage the uppermost tooth in its associated ratchet wheel to rotate the shaft the amount of one tooth which operates an adding and subtracting counter I52, the purpose of which will be presently explained. It is to be observed that solenoid I48 will rotate the shaft I43 in one direction while solenoid I49 will rotate it in the opposite direction to add or subtract to the counter.

'The soft iron solenoid core I53 of each of the solenoids I48 and I49 has an insulation blocker connector I54 riveted thereto and the forked member I46 or I41 are bolted thereto by bolt I55 (see Figure 19) The wiring diagram As previously stated, the current passes through wires I2 and I3 and through a switch I4 in the hot side of the line to the motor I5. To feed the solenoids a wire I is tapped off of the hot side I2 of the system and leads to one side of an electric light bulb socket I6I having an incandescentbulb I62 therein serving as a resistancei From theother side of the socket I6I a wire .I 63 is ledto one side of solenoid I26;

A wire I64 leads from the otherlsideof soles noid I26 to the uppermost leaf spring brush I22 shown in Figural. A hot wire I66 is tapped ofi of wire I63 and goes to one ofthe contactposts of solenoid I214and wire I 61 leads from the other contact post of solenoid I21 to the lowermost leaf spring member (I23 mounted oninsulation block.I2I and shown in Figure 1., r e P At this pointcit is seen that the two wires, can be grounded one at ,a time whenone of the contacts on plate I01 may engage oneof the. contacts I00 or IIlI on the insulation block 95 .because the plate I01 is grounded to the framework of the machine. A wire I10 is tappedoff of hot wire I63 and extends to one side of solenoid I48 and from the other sideof solenoid I48 a-wire 4| is connected to contact brush 38 in Figure 16.

A hot wire "I is tapped off of hot 'wire I10 and leads to one side of solenoid I49, and wire 40 leads from the other side of solenoid I49 .to the other metallic contact brush 39 in Figure 16.

Connected to the outer metallic band 33 (Fig. 6) on insulation block 3| is the wire .36, which as previously described, is connected to the leaf springcontact member 93 mounted on an insulation block I12 on the upper cage 'plate 46, which is adapted to be engaged by lever 84 when it is swung by contacting the cams ortprojectionsfllfl and BI to thereby ground the current and thus operate the counter in one direction, whereas wire 35 leads from the inner metallic ring 32' and is connected 'to metallic'contact leaf spring 92 mounted on insulationblock I13 on the upper cage plate 46 so that when lever engages cams and SH while rotating, it will forma contact to move the counterback in the other direction.

Method of operation In general, when the paddle [I5 i disposed in a fluid for testing the viscosity of the same, or when the brush H1 is resting on a surface, the smoothness of which is to be tested, or ,the size of a strand is being testedin groove I20A, or when the magnetic properties of an article I16 ar being tested by magnet I15, and switch I4 is moved to closed position, the motor I5 starts and this imparts rotation to the tube 25 and the cage thereon and this imparts torsion to the torsion wire 59 and through the torsion of this wire the lower tube 25A tends toberotated and until sufficient torsion builds up in the wire to overcome the drag on the tool, depending upon the viscosity of the material being tested or the moothness of the surface being tested, or broadly by the drag on the testing tool unit the torsion equals the drag on the tool, and. the tool will begin to move. The underlying principle of the operation is the sensing of the torsion in wire 59 necessary to actuate the tool, and the employment of this manifestation either as an index to measurement or for the purpose ofcontrol.

If the drag on the tool is greater than the torsion in the wire, then the contact I00 mounted on the tube 25A willvengage contact point I08 on the insulation block, rmountedon the tube 25, and thiswill cause a currenttofiow through solenoid. I21 by. means of wires I60, I63, I66 and I61 to,brush I23, which is in contact with. the

metallic ring 91 on the insulation block 95 mounted on the tube 25.. F v

Metallic ring 91 is connected to contact point I00 on the insulation block, which beingin contact with contact point I08 mounted on the disk I01 on tube 25A will ground the -circuit to the rramework of the machine andthus complete the circuit and solenoid I21 win be energized to-lower the sleeve 5| on the tube 50, which will cause the projections 90 and 91- thereon to'swing the lower lever 84- on the upper side of the cage plate 46- and thi will cause the current to flow in impulses through wire I60, I310, IIIs, solenoid I49, wire 40, brush 39, wire-- 35, and contact 93 where the circuit is grounded, and this wilt advance the counter one step for each one half revolution of the tube 25 or twice upon each revolution as the two earn 90 and 9|. will: swing the lever 84 two timesupon each revolution to convey impulses to the solenoid I49 to advance th counter, One or more projections. may be used on one sleeve 5|.

Each time the lever 84. i swung it. will ratchet the worm shaft 6|v one step at a time to move the worm wheel in the direction in which the cage .is rotating to thus increase the torsion on the torsion wire 59-. This moving step by step of the worm wheel will gradually increase the torsion in the torsion wir until the torsion in the wire equals the drag on the tool, at which time the contact point I08 on the lower tube 25A, will move away from the contact I on the insulation block 95 mounted on the lower end of the tube 25, to break the circuit to solenoid I21, and will allow the member I 33 mounted on the transverse rod I28, to swing to neutral position.

This will allow the cam sleeve having the projections 90 and SI thereon to swing to neutral position between the upper and lower levers 84 and 85 on the cage. plate 46. 'Thiswill continue until, for example, the viscosity of the material in the container becomes less or the liquid becomes thinner, or the surface over which the brush II! is disposed will have become smoother or the drag on the testing tool lessens, and in which case there will notbe as much resistance to the turning of the lower tube 25A by means of the torsion wire 59 and thus this. will cause the contact I09 on block I01 mounted on the upper end of the lower tube 25A to engage contact point IOI on the insulation block 95 mounted on the lower end of tube 25, which. will cause a current to fiow through wires I60, I63, solenoid I26, wire I64, and down to upper brush I22, which is in contact with the metallic band 96 on the insulation block 95 mounted on the lower end of the tube 25 and will ground the circuit through contacts IOI and I00 to energize solenoid I26, which will swing the member I33 pivoted on transverse rod I28 upwardly at the forward end next to the cage and thus raise the cam sleeve mounted on tube 50, which will cause the projections on the cam sleeve to be engaged by the upper lever 85 on the upper surface of cage plate 46, which will complete a circuit of two impulses each time the cage revolves through wires I60, I10, solenoid I48, wire 4|, brush 38, metallic band 33, and wire 36, contact spring 92 and back tothe other. side of the circuit, which is the grounded frame and thus delivers two impulses for each revolution to move the counter I48 in a subtracting direction and the swinging of the lever will continue until the torsion has been lessened in the torsion wire to a point where it is the same as the drag on the, tool, at which time the contacts IN and I09 will move apart, and thus break the circuit through solenoid j I26 and will cause the framework I29, mounted on rod I28, to swing to neutral position.

It is to be understood that this apparatus is to. be employed for continuously testing the viscosity of a fluid, or the smoothness of the surface of an object, or the magnetic properties of a piece of metal.

Where the testing tool would be equipped with a magnet I15, as shown in Figure 20, this could be employed in many diiferent fields such as, for example, in' rolling mills where a sheet I'I6 would be continuously passed by the magnet I15 or it could be employed for testing the various propcitiesof an object as to variations in magnetism or by moving the object relative to the magnet as, 'for example, in testing the hardness or softness of iron, steel and the like.

In the drawings and specification, there has been set forth a preferred embodiment of the invention, and although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention being set forth in the appended claims.

I claim:

1. Apparatus for testing a. substance comprising a torsion wire having a testing tool secured to. one end thereof, a constant speed driving means secured to the other end of the wire for imparting rotation to the said other end of the wire, means controlled by the drag imparted to the testing tool for increasing the amount of torsion in the wire to a point where the resistance imparted to the testing tool by the substance being tested equals the torsion in the, wire, and means for decreasing the amount of torsion in the wire when the testing tool encounters less resistance to rotation from the substance being tested.

2. Apparatus for testing an object comprising a torsion wire, a testing tool on one end of the wire adapted to test the object, means. connected to the other end of the wire for imparting rotation to the wire and to the tool carried thereby, and follow-up mechanism on the driving means responsive to variations in the torsion in the wire for imparting. further torsional movement to the wire, positive or negative, proportional to the resistance encountered by the tool.

3. Apparatus fcrtesting comprising a torsion wire having a testing tool on one end thereof, a constant speed driving means connected to the other end of the wire for imparting rotation to said other end of the wire and the tool carried thereby, means controlled by the amount of resistance ofiered to the rotation of the tool for rotating the wire at a faster rate than it is driven by the driving means for increasing the torsion in the wire, and means also controlled by the amount of resistance ofie-red to rotation of the tool for rotating the wire at a slower rate than it is being rotated by the driving means for decreasing the torsion in the wire.

4. Apparatus for testing an object comprising arotatable member and means for imparting rotation to the rotatable member, a torsion wire having one end secured to the rotatable member and a testing tool secured to the other end of the torsion wire, means controlled by the amount of torsion in the wire and while the tool is testing an object for rotating the wire in one direc tion at a faster rate than the rotating means are rotating to increase the torsion in the wire until the resistance offered by the object being tested to the testing tool equals the torsion in the wire, and means also controlled by the resistance offered to the testing tool by the object for rotating the wire at a lesser rate than the rotatable member to lessen the torsion in the wire when the resistance offered by' the substance to the rotation of the testing tool decreases.

5. Testing apparatus comprising a rotatable assembly, means for imparting rotation to the assembly, a torsion wire having one endthereof mounted in the assembly for rotation relative to the assembly, a testing tool secured to the other end of the wire for testing an object, means for imparting rotation to theiassembly to impart rotation to the wire and the tool carried thereby, means carried by the assembly for imparting rotation to the wire relative to the rotation of the assembly and while the assembly is rotating, means fixed on the wire and controlling the means for imparting rotation to the wire relative to the assembly to rotate the wire at a faster rate until sufficient torsion is imparted to the wire to cause the resistance offered by the object being tested to the testing tool to equal the torsion imparted to the wire, and other means fixed to the Wire for also controlling the means inthe assem bly. for imparting rotation to the wire in a reverse direction relative to the: assembly to decrease the torsion in the wire to where the torsion in thewire will counter-balance the resistance offered by the substance beingtested to the testing tool.

6. Testing apparatus comprising a rotatable tube, a cage assembly fixedly mounted on the tube, means 'for impartingrotation to the tube and the cage member, aiworm gear freely mounted on:the,tube and being adaptedto rotate independently of the jtube,1. a torsion member having its upper end fixedlyi securedto the worm, gear and extending through' the tube, a testing. tool assembly fixedlysecured on the other end of the torsion member andJbeingrestrained against rotation by the substance being tested, a pair of contacts fixed on the'testing tool assembly,the testing tool .1 assembly being fgrounded to the framework of the apparatus, apair "of contacts fixedly mounted on thetube to rotate therewith and insulated from the framework, a pair of movable members mounted in the cageiassembly, a worm rotatably mounted-in the cage assembly and meshing with the worm gear,means operable by the one of the movable members for-moving the worm in one direction and means operable by. the other movable member for moving the worm in the other direction, a sleeve member slidably mounted relative to the cage assembly and having a projection thereon, the two movablejmembersin the cage assembly being at different levels relative to: the projection on the sleeve and the projection on the sleeve being of such width that the movable members will'pass above and belowv the projection when the sleeve is ,in normal position, electrical means for movingthesleev'e member longitudinally of the axis of rotation of the cage assembly to cause one of the movable members to engage the projection to impart rotationto theworm in one direction to increase the torsion in the torsion member. until the torsion-,inithe. torsion member equals the drag exerted on the testing tool by the substance being tested, at which time a contact point on the testing tool assemblywill move away from a contact point on the tube :to 'break' the circuit toallow the sleeve to return to a'n'ormal position when the torsion in the wire equals the resistance offered to rotation of the testing tool assembly by the object being tested, a decrease in'the resistance offered to rotation of the testing tool by the object being tested servinggto "establish a second circuitto move the sleeve in the other the projection thereon to be engaged by the other movable member to rotate the worm and worm wheel in the opposite direction to decrease the torsion in the torsion member until the torsion in the torsion member equals the resistance offered by the object being tested to rotation of the testing tool.

'7. Apparatus for testing a substance as to viscosity, smoothness of surface, magnetic properties and the like, comprising a testing tool adapted to be influenced against rotation by an object being tested, a torsion member having one end thereof connected to the testing tool, constant speed means for imparting rotation to the other end of the torsion member, means controlled by the drag imparted torthe testing tool and operable while the torsion member is rotating for increasing the rotation of said other end of the torsion member above the rate of rotation imparted by the constant speed means until'the torsion in the torsion member equals the resistance offered to the rotation of the testing tool, and meansalso controlled by the drag imparted to the testing tool and operable while the torsion member and tool secured on one end thereof, driving means connected to the other end of the torsion member for imparting rotation to the torsion member and the tool carried thereby, and a follow-up mechanism responsive to variations in the torsion of the wire forimparting .afurther torsional movement to the wire, positive, or negative, proportional to the resistance encountered by the tool.

9. Apparatus for testing material to determine the amount of resistance offered to a tool-rotating under the influence of the material being tested, comprising a constant speed electric motor, a sleeve driven by the motor, a torsion wire having one end supported by the sleeve and having a testing tool fixedly secured on the other end thereof, and electrical means controlled by the amount of drag-offered -to the rotation of the testing tool by the material being tested for increasing the rate of rotation of the torsion wire beyond that imparted bythe motor until the torsion in the torsion wire equals the drag ofiered the rate of rotation ,of thewire below that .imparted by the motor when the drag on the testing tool decreases until the torsion in the wire equals the drag exerted on the testing tool.

10. Apparatus for testing a substance comprising a torsion wire having a testing toolsecured to oneend thereof constant speed means secured tothe other. .end oft-he wirezforcimpartmg rotation to theyvire', meansJfor-increasing the rate of rotation: of the wirebeyond thathimparted by the constant speed'means until the amountof torsion in the wire is increased to a point where the resistance imparted to the testing tool by the substance being tested equals the torsion in the wire, means for decreasing the speed of rotation of the wire below that imparted by the constant speed means when the testing tool encounters less resistance to rotation from the substance being tested, and means for indicating. the

direction relative to the, cage assembly to causeamount the torsion in theYwire-is increased or decreased over a given period of time.

11. Apparatus for testing an object comprising a rotatable member and means for imparting rotation to the rotatable member, a torsion wire having one end secured to the rotatable member and a testing tool secured to the other end of the torsion wire, means controlled by the amount of torsion in the wire and while the tool is testing an object for rotating the wire in one direction at a faster rate than the rotating means are rotating to increase-the torsion in the wire until the resistance offered by the object being tested to the testing tool equals the torsion in the wire, means also controlled by the resistance oifered to the testing tool by the object for rotating the wire at a lesser rate than the rotatable member to lessen the torsion in the wire when the resistance ofiered by the substance to the rotation of the testing tool decreases, and means for indicating the amount the torsion in the wire is increased or decreased.

12. Testing apparatus comprising a rotatable assembly, means for imparting rotation to the assembly, a torsion wire having one end thereof mounted in the assembly for rotation relative to the assembly, a testing tool secured to the other end of the wire. for testing an object, means for imparting rotation to the assembly to impart rotation to the wire and the-tool carried thereby, means carried by the assembly for imparting rotation to the wire relative to the rotation of the assembly and While the assembly is rotating, 1

means fixed on the wire and controlling the means for imparting rotation to the wire relative to the assembly to rotate the wire at a faster rate until sufiicient torsion is imparted to the wire to cause the resistance ofiered by the object being tested to the testing tool to equalthe torsion imparted to-the wire, other means fixed. to the wire for also controlling the means in the assembly for imparting rotation to the. wire in a reverse direction relative to the assembly to decrease the torsion in the wireto where: the torsion in the wire will-counter-balance the resistance offered by the substance being tested to the testing tool, and means for indicating the amount the wire is rotated relative to the assembly.

13; Testing apparatus: comprisinga rotatable tube, a cage assembl'y fixedly mounted on the tube, means for imparting rotation to the tube and'the cage member, a worm gear freely mounttation by the substance being tested, a pair of contacts fixed on the testing tool assembly, the testing tool assembly being grounded to the framework'ofthe apparatus, a pair of contacts fixedly mounted on thetube to rotate therewith and insulated from the framework, a pair of movable members mountedinthe cage assembly, a Worm rotatably mounted in the cage assembly and meshing with the worm gear, means operable byv the one of the movable .members for moving the worm in 'one direction and means operable by the other movable member for moving the worm in the other direction, a sleeve member slidably mounted relative tothe cage assembly and having a projection thereon, the two movable members in the cage assembly being atdifferent levels relative to the projection on the sleeve and the projection on thelslee've' being of such width that the movable members will pass above and below the projection when the sleeve is in normal position, electrical means for movingthe sleeve member longitudinally of the axis of rotation of the cage assembly to cause oneof the movable members to engage the projection to impart rotation to the worm in one direction to increase the torsion in the torsion member until the torsion in the torsion member equals the drag exerted on the testing tool by the substance being tested, at which time a contact point on the testing tool assembly will move away from a contact point on the tube to break the circuit to allow the sleeve to return to a normal position when the torsion in the wire equals the resistance offered to rotation of the testing tool assembly by the object being tested, a decrease in the resistance ofiered to rotation of the testing tool by the object being tested serving to establish a second circuit to move the sleeve in the other direction relative to the cage assembly to cause the projection thereon to be engaged by the other movable member to rotate the worm and worm wheel in the opposite direction to decrease the torsion in the torsion member until the torsion in the torsion member equals the resistance ofiered by the object being tested to rotation of the testing tool, a counter, and means controlled by one of the movable members for moving the counter in one direction when the movable member is moved and means controlled by the other movable member for moving the counter in the other direction when the movable member is moved.

14. Apparatus for testing a substance as to viscosity, smoothness of surface, magnetic properties and the like, comprising a testing tool adapted to be influenced against rotation by an object being tested, a torsion member connected to the testing tool, means for imparting rotation to the torsion member and the testing" tool carr'id thereby, means operable while the torsion member is rotating for increasing the torsion in the torsion member until the torsion in the torsion member equals the resistance offered to the rotation of the testing tool, means also operable while thetorsion member and testing tool are rotating for decreasing the torsion in the torsion member when the resistance ofiered to rotation of the testing tool decreases, until the torsion in the torsion member equals the resistance offered to rotation of the testing tool, and means for indicating the amount the torsion is increased in the wire and means for subtracting from that amount the amount the torsion is decreased in the wire.

15. Apparatus for testing the drag ofiered to a rotary testing tool by a material being tested comprising a torsion member having a testing tool secured on one end thereof, constant speed driving means connected to the other end of the torsion member for imparting rotation to the torsion member and the tool carried thereby, means operable while the torsion member is rotating for increasing the torsion in the torsion member until the torsion therein equals the drag oflered by the material to rotation of the testing tool, means for decreasing the torsion in the torsion member when the drag on the testing tool decreases until the torsion in the torsion member equals the drag being exerted on the testing tool, and means operable by the means for increasing the torsion for indicating the amount the torsion isfincreased and means operable by the means for decreasing the torsion for'subtracting from means for indicating the amount of variation in the torsion over a given period.

1'7. Apparatus for testing material to determine the amount of resistance offered to a tool rotating under the influence of the material being tested, comprising a constant speed electric motor, a sleeve driven by the motor, a torsion wire having one end supported by the sleeve and having a testing tool fixedly secured on the other end thereof, electrical means controlled by the amount of ,drag ofiered to the rotation of the testing tool by the material being tested for increasing the torsion in the torsion wire until the torsion in the torsion wire equals the drag offered to rotation of the testing tool and for decreasing the torsion in the wire when the drag on the testing tool decreases until the torsion in the wire equals the drag exerted on the testing tool, and means for indicating the amount the torsion has been increased and means for subtracting from said amount the amount the torsion has been decreased.

JOHN M. BELL. 

